In recent years, flexible line rotary garden cutters have been popularized. Such cutters utilize a rotating hub with lines attached to the hub periphery. The statically flexible lines form a semi-rigid blade when rotated at high speed. The efficient cutting capability of such flexible line cutters has been successfully demonstrated. If the lines encounter relatively rigid objects, the filaments yield. Accordingly, all else equal, flexible line cutters are less hazardous than cutters utilizing rigid blades.
The flexible line has a relatively short life. Replacement is often necessary. The Geist and Ballas patent suggests the use of storage spools with releasable wedge locks whereby the line can be renewed. Another arrangement suggested by Geist and Ballas is one in which the precut line lengths are tied at apertures in the rotating hub. The wedge lock and spool arrangement is not entirely satisfactory because there is no positive control of the length of the line. The operator tends to use too much or too little line, violating the optimal relationship between line radius and rotational speed. The precut and tie arrangement maintains the optimal relationship of line length or radius to rotational speed, but the operations necessary to untie the old line and tie the new line is quite cumbersome.
The primary object of the present invention is to provide a flexible line cutter in which the worn line is easily removed and new sized line readily installed.
In known prior art devices, the line may be broken if it is caught between the rotary hub and a relatively rigid object, such as stonework or curbing. Another object of the present invention is to provide simple means for protecting the line from such hazard whereby the already short life of the flexible line is not further imperiled.
Another object of the present invention is to provide a releasable clamping device for pre-sized line that gently, yet firmly clamps the line in position without imposition of excessive localized stress.